Ore extraction



Dec. 24, 1940. A, ELlAN EI-AL 2,226,164

CRE EXTRACTION Fled March 10, 1938 2 SheeffS-Seei l wld ATTORNEYS Dec. 24, 1940. A, J EUAN ETAL 2,226,164

ORE EXTRACTION Filed March 10. 1938 2 Sheets-Sheet 2 INVENTORS //f/Yu r J. Elia?? @fr ATTORNEYS Patented Dec. 24, 1940 ORE EXTRACTION Arthur J. Elian and Charles F. Prraga, Mexico,

D. F., Mexico, assignors to Vacuum Process Extraction Corporation, a corporation' of Dela- Ware Application March 10, 1938, Serial No., 195,073

17 Claims.

'15 Other objects will appear in the yfollowing description, reference being had to the drawings in which:

Fig. 1 is a partial section of the apparatus taken on line I I of Fig. 2.

Fig. 2 is a section taken on the line 2 .f 2 of Fig. l, the power driving `mechanism being omitted for clearness of illustration.

Fig. 3 is a development in diagrammatic form showing the operation more clearly.

-2' Fig. 4 is a diagrammatic illustration of the operating cycle.

Referring to Fig. 1, the tank l is adapted to contain a mixture of disintegrated ore and cyanideI solution. It may be supported in any Way such as on beams 2 extending across between foundationsr 2'. A pair of vertical angle irons 3 and 4 are welded or otherwise secured to the tank at each side to support the upper driving gears and shafts generally indicated at 6. The '35 lower driving gears and shafts are generally indicated at 1. The purpose of these two separate drives will be later described.

At the bottom of the tank I is an agitating de- Vice 8 which by way of example we have shown' as a circular disk of metal having projecting vanes 9 to give an impeller action. This agitator is fastened to a rotatable shaft ID journalled in bearings II, II. packing gland with a suitable screw plug I2 to j. make the bearing watertight. This agitator is rotated by the gear mechanism 1 connected to power drive I3. Alternatively the driving gears may be located at the top of the tank with avoidance of the packing gland.

A deflector or scoop I4 is mounted in inclined position on an arm I5 fastened to a tubular shaft I6 extending over but out of contact with the upper end of shaft I0. The tubular shaft I6 may have a sealing plug I8 so that air pressure sup- -55 plied to theupper part of the tube, as hereinzinc shavings or particles.

leachingchambers. v

The upper bearing II has a v (o1. 21o- 153)y yafter morefully described, will not pass down through the tubeA and out of its lower end. Any other arrangement may be usedV to accomplish the same purpose. f

The tubularshaft passes through one or more `5 bearing members I9 of ball bearing or any desired type and is connected to the gear mechamsm-6 hereinbefore mentioned. The pipe connection leads into the upper part of the shaft I6 and terminates in an air nozzle 2| directed 10 upwards at an angle. Compressed air is admitted to theinterior of rotatable pipe I6 by pipes 22 and 23, the former being stationary and the latter, being rotatable ,with shaft I6. Pipe 23 is threaded into a plug `24 screwed into -15 the .top of tube I6. A packing gland 25 surrounds the adjoining ends of pipes 2 2 and-23 with packing 25 land compression nut 26 to pre'- Vent escape of air at the joint. Any desired air Pressure may be used but We have found thirty -Zro r pounds or over more suitableufor the purpose.

Above the rotatable deector and air nozzle ,are arranged a series of leaching chambers 21. vEach chamberconsists of a cone shaped housing `open` at they bottom: l,filter medium 28 of canvas or other suitable ma# 4terial. The arrangement is preferably such that The bottom is closed by a i" this filter mediumisflat and horizontal. To make the lter medium rigid a supporting grill 29.is secured to the open end of the housing and the filter medium is stretched tightly across this su grill. Each housing has a suction pipe 30 lead- Aing fro-mits toputo a suction ring 3|. 'suction ringis connected by a suctionpipe 32 to precipitation chamber 33 containing theusual The general arrange- 35 ment is shown diagrammatically` in Fig. 4. A vacuum pump 34, is connected with the precipitationrjchamber by pipe 35 so that a suitable vvacuum is maintained in the suction line and The operation of our improvement may now be described.

The tank is charged with pulp or mixture consisting of V,disintegrated ore'and cyanide solution, the tank should Ate' suon that it will .not reach 45 the filter mediums either, Whengit is quiescent .through pipe 36. 'I'he height of the mixturein .or When itl isxthrownup into va vortex by the kagitator V8 ashereinafter described.- With the shaftsandgears generally indicated at 'Lfrotatf Ting, lsay 'in gthe `directionindicated by the arrow vA, the agitatorilwill be .rotated to the' left as viewedirrFig.:1.` The belt 31 will then rotate the gears andfshaft arrangementgenerally indicated a-t 6 in the direction indicated by the 55 arrow B. This rotates the defiector or scoop I4 to the right as viewed in Fig. l. The rotation of the agitator draws the mixture downward at the center and throws it out against the sides of the tank where it flows upwards and then downwards towards the center again. The agitator also gives the mixture a rotary motion to the left. The agitatorthus maintains the mixture in a vortex.

As the deflector or scoop revolves to the right with its lower edge immersed in the mixture the combined action of the rotating vortex and the reversely rotating scoop forces a stream of mixture upwards along the scoop `and into contact with each of the filter mediums in succession. The vacuum draws the cyanide-metal solution through the filter medium as soon as the mixture strikes the filter cloth and causes a-thin lter cake 31 to adhere thereto. 'Ihe thickness of the adhering cake is exaggerated in Fig. 3 Vfor purposes of illustration. -As the agitator-sweeps around and the scoop lforces the mixture into enigagement with the filter mediums in rapid .succession the vacuum draws outthesolution contained in the thin layers of adhering filter cake :which thus 'become :substantially dry but which 'still have adhering layers of pregnant solution particularly on thebottom sides of the ore particles and inthe minute crevices land irregulari- `|ties of the particles. The moving, upwardly directed air jet 2l sweeps along'behind the scoop under the-substantially dryiilter cake and the air pressure greatly aids the vacuum in stripping the iilter cake of its lastvestige of adhering iilm of pregnant solution which byits position cannot be sucked out by the vacuum. We have found this final stripping action of the air jet very important Vand that it adds ygreatly to the efficiency and speed of the operation. Eachtime'the scoop throws the mixture against the lter a thin lm adheres until a certain thickness is reached when gravity and the force ofthe air jet dislodge, as at 'C of Fig. 3, -a partyor all, of theadhering cake. By the combined action of gravity and the air jet this adhering layer is limited to a Adeiinite thickness which is always -suflicently thin to permit the Vacuum to function with full efficiency. As the operation continues the agitator stirs up the mixture and new portions are repeatedly brought into intermittent engagement with the lter mediums in succession. The combined action of the vacuum and Vair jet is such that after a relatively short run the valuable content -is almost entirely removed and the worthless sludge can then be discharged, for example, through pipe 38. vThe tank-is then recharged-and theoperation repeated.

Fresh barren cyanide solution is admitted from tank 39 as fast as the pregnant solution is withdrawn through `the leachers. The barren solution after leaving precipitation chamber 33 is led into storage tank 40 where it is pumped back into tank 39 by a suitable pump'4 I In practice this system of extraction has proven to be remarkably eilicient in recovery of gold and silver from theirores both as to percentage of recoveryand time involved. The extraction is exceptionally complete and thetime involved is remarkably short. We have been able `to get of the gold in a three hour run and practically all of it in fteen hours. We have Valso found that goldand silver can be readily extracted from ores containing manganese compounds which heretofore :could not be satisfactorily worked by the cyanide process.

We have shown a particular form of agitator and one scoop and air jet but this is by way of example only. The mixture may be agitated in any way and there may be any desired number of scoops and air jets. Also, various ways may be 5 used to intermittently raise the mixture against the lilters. These and various other changes may be made without departing from the spirit of the invention.

Having described our invention, what we claim is:

1. In ore extraction apparatus, a tank adapted to ycontain a mixture of disintegrated ore and an extraction-solution, a leaching chamber in the tank positionednormally above the level of the solution theren,.a suction pipe connected to the leaching chamber, a filtering medium in the bottomoi theleaching chamber, means for agitating the mixture beneath and out of contact with the ltering medium, and means to intermittent. ly bring themixture and the under surface fofsaid vfilter into .and out of `contact with eachother.

2. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated vorefand an extraction solution, a .leaching chamber in .the tank positioned normally above the level .of the mixture therein, a `suction pipe connected tothe leaching chamber, a ltering mediuminthe bottom of the leaching chamber, an .agitator for stirring the mixture beneath and koutsof contact with the ltering medium, .means to .intermit- .tently bring :the mixture and the under surface of said ltering `mediuminto .andout of contact with each other, and `means for fdirecting air under pressure against vIilter .cake adhering to the under surface of thezfilter.

3. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore andan extraction solution, na ileachingchamber in the tank ,positioned .normally above the level of the mixture therein, iasucticn pipe connected to the leaching chambena lteringmediumjn thefbottomof the leach-ing chamber, means foragitating and moving the Amixture beneath and out of contact with the filtering medium, and means to intermittently raise the mixture against :the under surface of said lter.

5l. In ore extracticnapparatus, ia `tank adapted to contain a Ymixture of disintegrated ore and an extraction solution, a plurality'ofleachingchambers in the tank 'positioned normallyzabove the -level of the mixture therein, a suction pipe connected -to the leaching chambers, a ltering medium .in the bottoms of the leaching chambers, an agitator for moving the imixture beneathand out of contact with the :filtering mediums, a defiector for intermittently raising the mixture yagainst the under surfaces of said filters, and means Vfor directing air under pressure against the lter cake adhering vto the under surfaces of `the lters.

5. Inore extraction apparatusa tank adapted to cont-aina mixture of disintegrated ore and an `extraction solution, a plurality of leaching chambers in the tank positioned normally above the level of the mixture therein, a suction pipe connected to the leaching chambers, a filtering medium in the bottoms of the lea-ching chambers, an agitator for moving the mixture in one :direction beneath and out of contact lwith the ,filtering mediums, Aa de'flector adapted to .move .in the opposite direction for intermittently raising the mixture vagainst the under surfaces of said lters, and an air duct Vbehind the deilector and moving in unison therewith, for directing air `against the 75 filter cake adhering to the under surface of the filter.

6. .In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore and an extraction solution, a plurality of leaching chambers in the tank positioned normally above the mixture therein, filtering mediums on the under sides of said leaching chambers, suction pipes connected to the leaching chambers for withdrawal of solution therefrom, an agitator in the tank below the leaching chambers, an inclined scoop above the agitator having its lower edge adapted to be in the mixture and its upper edge under and adjacent the filtering mediums, and means for rotating the agitator in one direction and the scoop in the opposite direction for raising the mixture against a filtering medium when the scoop passes thereunder.

7. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore and an extraction solution, a plurality of leaching chambers in the tank positioned normally above the mixture therein, filtering mediums on the under sides of said leaching chambers, suction pipes connected to the leaching chambers for withdrawal of solution therefrom, an agitator in the tank below the leaching chambers, an inclined sooo-p between the agitator and the leaching chambers having its lower edge adapted to be in the mixture, and means for rotating the agitator in one direction and the scoop in the opposite direction for raising the mixture against a filtering medium when the sco-op passes thereunder.

8. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore and an extraction solution, a plurality of leaching chambers in the tank positioned normally above the mixture therein, filtering mediums on the under sides of said leaching chambers, suction pipes connected to the leaching chambers for withdrawal of solution therefrom, an agitator in the tank below the leaching chambers, an inclined scoop above the agitator having its lower edge adapted to be in the mixture and its upper edge under and adjacent the filter mediums, means for rotating the agitator in one direction and the scoop in the opposite direction for moving the mixture up the scoop against a filtering medium when passing thereunder, and an air nozzle trailing the scoop in the fixed relation thereto for directing air against filter cakes adhering to the under surface of the lter mediums.

9. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore and an extraction solution, a leaching chamber in the tank positioned normally above the level of the solution therein, a suction pipe connected to the leaching chamber, a filtering medium in the bottom of the leaching chamber, and means to intermittently bring the mixture and the under surface of said filter into and out of contact with each other.

10. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore and an extraction solution, a plurality of leaching chambers in the tank positioned normally above the level of the mixture therein, a suction pipe connected to the leaching chambers, filtering mediums in the bottoms of the leaching chambers, a deflector adapted to rotate within the tank and below the leaching chambers for intermittently raising the mixture against the under surfaces of said filters, and an air duct behind the deiector and moving in unison therewith for directing air against the filter cake adhering to the under surface of the lter.

' 11. In ore'extraction apparatus, a tank adapted to contain a mixture o-f disintegrated ore and an extraction solution, a leaching chamber having an horizontally positioned filter in the bottom thereof, means to draw pregnant ksolution upwardly through the filter and out of the chamber., and an independent continuously operating fluid jet adapted to direct fluid under pressure intermittently against ore particles adhering to the lower surface of the filter.

12. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore and an extraction solution, a leaching chamber in the tank positioned normally above the level of the mixture therein, a suction pipe connected to the leaching chamber, a filtering medium in the bottom of the leaching chamber, means to intermittently bring the mixture and the under surface of said filtering medium into and out of contact with each other, and means for intermittently directing a jet of fluid against the under surface of the filter.

13. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore and an extraction solution, a leaching chamber in the tank positioned normally above the level of the mixture therein, a suction pipe connected to the leaching chamber, an horizontal filtering medium in the bottom of the leaching chamber, a deflector adapted to rotate within the tank and below the leaching chamber for intermittently raising-the mixture against the under surface of said filter, and a fluid duct behind the defiector and moving in unison therewith for directing fluid against the under surface of the filter.

14. In ore extraction apparatus, a tank adapted to contain a .mixture of disintegrated ore and an extraction solution, a plurality of leaching chambers in the tank positioned normally above the level of the mixture therein, a suction pipe connected to the leaching chambers, a filtering medium in the bottoms of the leaching chambers, an agitator for moving the mixture beneath and out of contact with the filtering mediums, a deflector for intermittently raising the mixture against the under surfaces of said filters, and means for intermittently directing fluid under pressure against the under surfaces of the filters. 15. In ore extraction apparatus, a tank adapted to contain a mixture of disintegrated ore and an extraction solution, a leaching chamber closed at thel top and having an horizontal lter in the bottom thereof, a suction pipe connected to the leaching chamber to draw pregnant solution upwardly through the filter and out of the chamber, and means for removing filter cake from the lower surface of said filter while pregnant solution is being drawn through the lter comprising a duct for directing iiuid' under pressure intermittently against the lower surface of said lter.

16. In ore extraction apparatus, a tank adapted to contain a mixture lof disintegrated ore and an extraction solution, a leaching chamber closed at the top and having an horizontal filter in the bottom thereof, a suction pipe connected to the leaching chamber to draw pregnant solution upwardly through the filter and out of the chamber, and means for removing filter cake from the lower surface of said filter while pregnant solution is being drawn through the filter comprising a duct for directing fluid under pressure intermittently against the lower surface of said filter, said duct being located outside of said leaching chamber.

17. In ore extraction apparatus, a tank adapted to contain a mixture 'of disintegrated ore and .an extractionsolution,l a plurality of leachingvchambers, each chamber'being closed at the top and lia-ving an horizontally positioned iter in the bottom thereof, a suction pipe connected to the leaching chambers to draw pregnant solution upwardly through the filters and out of the chambers, and means for removing filter cake from the lowersurfaces of said filters While pregnant solution is being drawn through the lters comprising a moving duct for directing fluid under pressure successively against the under surface of each iter.

ARTHUR J. ELIQN. CHARLES F. PARRAGA. 

